1. Field of the Invention
The invention relates to an electronic conference system using a network and a database and, more particularly, to an electronic conference system in which a person who participates in a conference halfway can grasp the proceeding of the conference in a short time. The invention also relates to an electronic conference system in which after the end of a conference, the participants of the conference can immediately get a summary of the conference.
2. Description of the Prior Art
Hitherto, an electronic conference system using a number of terminal devices connected to a network has been known. As such an electronic conference system, there is a case where it is provided as one function of a telecomputing or personal computer communication such that the user communicates with a host computer by a personal computer at home or in a company via a telephone line or a dedicated line or the user receives information services from a provider. In the telecomputing or personal computer communication, there is a mechanism called a forum or SIG [special interest group] as a place where opinions or information about a common subject is exchanged. A library is provided for such a mechanism and messages posted in the electronic conference, programs, and data are recorded. A message, an opinion, a criticism, a supplement, an annotation, or the like which is added by another person to information written in an electronic conference room or on an electronic notice board is called a [comment]. A behavior to add a comment or an answer to the original message is called a [follow]. What is obtained by connecting only the follow to the original messages is called a comment tree or thread. What is obtained by making a list of only threads for a certain message can be handled as proceedings of its discussion.
In the electronic conference system by those conventional techniques, as the number of messages of the user of the system increases, the relation between the messages becomes complicated. Since a reply message which responded to a certain message is posted by citing the messages which were posted before, a sentence of the same contents appears by a plurality of messages. The user who uses the electronic conference system is hard to understand a corresponding relation of the message contents.
In the case where the user who uses the electronic conference system in the conventional technique newly participates in an electronic conference in which the discussion has been proceeded to a certain extent, it is necessary to see all of the messages which have already been posted.
Generally, when it is necessary to read a large quantity of document, a system for summarizing sentences and extracting important portions is demanded for the user and many studies regarding the techniques to summarize sentences have been performed so far.
However, a system which can summarize a document having a hierarchical structure and including quotations like an electronic conference is not known. As a conventional technique regarding a system for summarizing a single sentence, a technique disclosed in JP-A-4-74259 "Document summarizing apparatus" is known. The above technique discloses a technique for morpheme analyzing a sentence as a target to form a summary every sentence and discriminating an important sentence on the basis of character decoration information added to the characters, for example, information such as underline, mesh, emphasis, or the like added to the characters. Even if such a conventional technique is tried to be applied to an electronic conference system to which the invention is applied, when character decoration information is not added, a discussion is not summarized.
In the electronic conference system to which the invention is applied, what is called, an electronic conference system such that the number of messages increases as the discussion proceeds and, in association with it, a degree of complexity of the structure of the discussion tree increases such that a path of the discussion is branched or the like, a technique to effectively form a summary of the discussion is not known. Therefore, in the conventional technique, when it is desired to know the summary of the discussion in the halfway or after the end of the discussion, it is necessary to read all of the messages. There are, consequently, a problem such that it takes time to understand the contents of the discussion and it is difficult to efficiently grasp the contents.